As integration of integrated circuit devices increases, line widths of wires may be reduced, and an amount of current per unit area, that is, a current density, may be increased. However, conventional metal wire may be limited to a minimum width of about 70 nm, and the maximum current density may be about 106 A/cm2. Currently, nano lines such as carbon nano tubes may provide a wiring substance having a relatively high current density at smaller line widths than that of metal wires.
Some methods of forming nano lines on a substrate may be classified into methods of directly synthesizing nano lines on a substrate using a catalyst layer, and methods of arranging synthesized nano lines on a substrate. Examples of methods of arranging nano lines on the substrate may include an air flow method, an electrical field method, a magnetic field method, a microfluidic flow method, a mechanical force manipulation method, and/or a Langmuir-Blodgett method.